There are known simultaneous displacement devices for sliding doors with only two sliding leaves, both with the ability to simultaneously move in the same direction and sense. To that end, the first sliding leaf is hung from an upper guide through a couple of moving carriages which slide inside it and from which there hang skids integral to a bearing profile holding said leaf. The second sliding leaf is hung in the same way through a second upper guide parallel to the first leaf. In order to carry out the simultaneous displacement of both leaves, the first one of them features a cogged belt arranged between two pulleys integral to the bearing profile. Each one of the pulleys is located at one of the side ends of the first sliding leaf, so that the belt extends along the whole width thereof. The belt is engaged at a fixed point of reference, generally a part anchored to the ceiling, next to the upper guides, while the second sliding leaf is engaged to said belt. In this way, when the sliding of the second sliding leaf starts to pull from the belt of the first leaf, which, as it is anchored to a fixed point, in turn pulls from one of the pulleys thus producing the simultaneous displacement of both sliding leaves.
The simultaneous displacement device described above has important limitations and inconveniences. The main limitation is that it only allows the simultaneous sliding of two sliding leaves running in the same direction and sense. That is, it does not work with sliding doors the leaves of which run in a synchronized manner in opposite senses. This limitation makes the device described above to be intended to a limited number of applications or uses. Specifically, for its application or use in sliding doors which have a relatively small free passage width. As regards the inconveniences, it is noted the mounting complexity of the device described above, since it implies both the installation of an upper guide for each one of the two sliding leaves and the installation of the anchoring part of the cogged belt, among other elements.
In the field of sliding doors for lifts are known other simultaneous displacement devices, such as those ones described in DE9416316 and U.S. Pat. No. 4,781,270. Those sliding doors comprise a first and a second sliding leaves hung from an upper guide, and which have the ability to run in its direction. Their simultaneous displacement devices comprise a first cogged belt enabled for the union of the first sliding leaf, by means of brackets or support frames. The first and the second cogged belt are established between a first set and a second set of cogged pulleys respectively. The first set and the second set of pulleys are fixed on a first and a second axis respectively, so the sliding doors never move separately.
The present invention solves the problems described above in a fully satisfactory manner thanks to a device which has great application flexibility and simplicity. Specifically, the device of the present invention allows both the simultaneous displacement of two sliding leaves moving in the same direction and sense, and the simultaneous sliding of three and four sliding leaves running in the opposite sense to that of the two first leaves in a synchronized manner. All main elements configuring the device are integrated in an upper guide with easy installation and mounting.